216 PROCEEDINGS OF THE ACADEMY OF 



chevron, directed forwards. The strife are not so closely placed as in U. p e c- 

 ti n atu s , but are separated by grooves wider than themselves. 



The humerus, ulna, and radius are rather stout, and of a size relative to the 

 body, as in common types of existing Sauria ; the ulna and radius separate. 

 There is no carpus, but five well-developed digits have phalanges in tlie follow- 

 ing numbers, commencing on the inside : 3 — 4 — 5 — 6 — 5. The last phalange 

 of the second is obscured, and it is not positive that the number is as given ; 

 it is more probable than that it should have been 3. The outer toe has been 

 more slender than the others ; the distal phalanges of all the toes are short 

 conic, as in Salamanders. Thus this form differs much from Ampliibamus, 

 where the numbers are 3 — 3—4 — 5 — 4, showing a lower developement of 

 limbs. 



The ribs are long and curved, as in Reptiles, and judging by their distances 

 the vertebra are short ; the latter are not well defined, but there is no indica- 

 tion of prominent spines of any kind. 



The pelvic bones and portions of those of the hind limbs are present, but so 

 obscure and confused as not to be made out. Enough remains to show that 

 the hind limbs are considerably larger than the anterior. 



Sauropleura dictITata Cope. 



Tliis species had a length of body about equal to that of a fully-grown Cha- 

 mteleo vulgaris of the largest size, or of a half-grown Menopoma. Thirteen 

 ribs on one, and several on the other side, are preserved ; where they terminate, 

 probably at the pelvic region, some small or rudimental ribs project from the 

 two or three first caudals. Three ribs and their interspaces extend over five 

 lines. The humerus is broken, but its length can be clearly made out to be 

 seven lines ; it has no condyle, and is dilated at both extremities. The ulna 

 and radius are distinct, truncate, hollow, and dilated at the ends. Length of 

 ulna 5-1 lines, distal width 1-8 lines. Carpus not ossified. The fourth toe is 

 considerably longer than tlie others, the fifth is next, and reaches tlie basal 

 third of the antepenult phalange of the fourth ; the third is very little shorter ; 

 the first is not quite so long as the first two of the third. The bones of the 

 hind limb are not readily distinguished. Thej' are evidently much longer and 

 larger than the anterior; no part of a foot is preserved. 



This form is probably allied to Urocordylus. It has relatively much stronger 

 ribs in relation to the vertebrie than we have seen in that genus, and there is 

 no evidence of the existence of the peculiarly formed spines of the vertebriB 

 characterizing the latter. The limbs are relatively much stronger than in 

 Ophiderpeton, and it lacks the peculiar dermal armature of that genus. 



Sauropleura pectinata Cope. 



This species is represented by portions of the vertebral columns of four indi- 

 viduals. In two of these, vertebral centra are discoverable; in one quite defi- 

 nitely. They are slightly coiastricted medially, and without ridge or j)ro(^s. 



The neural and haemal spines of superior and inferior lines are similar, and 

 in the specimens undistinguishaljle. The dilated portions forin nearly equi- 

 lateral triangles, which stand on moderately short pedicels. They are weakly 

 ridged, and each ridge is prolonged into a narrow acute tooth, beyond the 

 margin, of which eleven may be counted on one of the best preserved. The 

 longitudinal striiB are terminated near the pedicel by two others, which cross 

 obliquely from each side, and, meeting, present an appearance similar to an 

 overlapping of each margin. The edges of the spines form a continuous line. 



As in the other species, there are no indications of other processes, nor of 

 dermal scales. 



The smallest of the specimens shows that in front of the region furnished 

 with the peculiar spines described, the body is furnished with a mass of bristle- 

 or hair-like scales. The grooved neural spines are slightly displaced anteri- 

 orly, and the bristle-like mass looks like a continuation of their striaj, and it is 

 not easy to find any line of demarkation between them. Tlie serrate spines are 



[SeiJt. 



